Fuel Gauge always shows 1/4 full

[steveg]

I've used this stuff with good results:

https://www.amazon.com/Permatex-854...t=&hvlocphy=9032277&hvtargid=pla-571817582075

It feels and smells a lot like Hylomar. I have a BN2 with an aftermarket tank which has a poorly made sender flange; finally stopped the leaking with two cork gaskets with a thin smear of this.

Permatex sold (made?) Hylomar for a while. Maybe they reverse-engineered it for this product.

PS - a question answerer on Amazon says Permatex purchased Hylomar Co. and brought this product out soon after. From the reviews & comments, it's clear Permatex needs to do a better job of explaining this product. People are complaining about it taking forever to set up.

 

[BJ8Healeys]

Steve - see: https://tinyurl.com/y4pvkmzp - examine the sender orientation and whether you have a sunk float.

Steve, your illustrations show that the correct orientation of the sending unit float arm is TOWARD the front of the tank in order for the float and sending unit to work properly. However, the illustration can also mislead someone into judging the position of the float arm by the orientation of the sending unit terminal. Your illustration shows the float arm FORWARD, but the terminal toward the REAR of the car. The original orientation of the terminal and float are both toward the front of the car. I have two Moss replacements, and both of those also have the terminal and float toward the FRONT. From the shape of your float arm, I take it that there is a replacement available that has moved the terminal to the other side of the sending unit body.
So, do not rely on the position of the terminal to tell you which way the float arm is pointing.

 

[steveg]

Steve, your illustrations show that the correct orientation of the sending unit float arm is TOWARD the front of the tank in order for the float and sending unit to work properly. However, the illustration can also mislead someone into judging the position of the float arm by the orientation of the sending unit terminal. Your illustration shows the float arm FORWARD, but the terminal toward the REAR of the car. The original orientation of the terminal and float are both toward the front of the car. I have two Moss replacements, and both of those also have the terminal and float toward the FRONT. From the shape of your float arm, I take it that there is a replacement available that has moved the terminal to the other side of the sending unit body.
So, do not rely on the position of the terminal to tell you which way the float arm is pointing.

Steve, thank you for good advice re the terminal orientation. There are two different senders - the pre-BJ8 model, which I show above, has front-float & rear terminal; the BJ8 model has both float and terminal on the front. IIRC this was discussed in an older thread. Moss shows two PNs: 021-590 & 021-591.

 

[DTDuck]

Hi John
Wouldn't I have the same situation with a gasket there? Actually not sure where the tank is grounded so will go and look.
If I do attempt to remove the sender I wonder if the silicone will peel off or whether I would end up picking at it with the danger of bits falling into the tank.
I will check the ground situation but if that doesn't help i'm inclined to keep using the measuring stick.
thanks
Steve

Not necessarily, with just a gasket the screws that hold the sending unit in place go cleanly through the gasket into the metal of the tank. On the other hand if, when they put the silicone in, they slopped it on good enough it may have gotten on the screws insulating them. The actual grounding of the tank was originally through the metal fuel line that goes to the fuel pump. This arrangement can be iffy after years due to corrosion, just bad connections, or if any section of the line has been replaced or repaired with rubber hose. The simplest (and most effective) way to ensure a good ground is to run a single wire from one of the screws on the sending unit directly to the chassis or body. Just remove one of the screws on the top of the sending unit, use a ring terminal at either end. Replace the screw through the ring terminal on the sending unit and either a body screw if you can find a convenient one or a sheet metal screw if not. It's an easy job and it should give a very reliable ground.

As far as removing the silicone, it should peel off fairly easily but if you are worried about it falling inti the tank you can hold a rag in the opening while you are peeling it off to minimize the chances of this happening. Note starting with an almost empty tank will make it easier.

Cheers,
Dan M.

 

[BJ8Healeys]

Steve, I only know BJ8s. My comment was prompted by questions I've seen in other forums before about "which way should the sending unit terminal point?" I don't recall any responses that it depends on the model, but now I know.
Thanks!

 

[steveg]

The important thing is that the float go toward the front.

IIRC the BJ8 fuel gauge must have a different resistance range than the others, hence the different sender.

 

[Bob_Spidell]

Permatex sold (made?) Hylomar for a while. Maybe they reverse-engineered it for this product.

PS - a question answerer on Amazon says Permatex purchased Hylomar Co. and brought this product out soon after. From the reviews & comments, it's clear Permatex needs to do a better job of explaining this product. People are complaining about it taking forever to set up.

I believe it is supposed to remain tacky; i.e. not set up (are some not aware of that?). I believe there at least 2 types of Hylomar, and one is 'better,' but I couldn't tell you which one (and not because I'd have to kill you ).

 

[steveg]

I believe it is supposed to remain tacky; i.e. not set up (are some not aware of that?). I believe there at least 2 types of Hylomar, and one is 'better,' but I couldn't tell you which one (and not because I'd have to kill you ).

That's what I mean - folks saying it's a ripoff because it never sets up. Not realizing it's supposed to be that way.
Permatex not sufficiently explaining the benefits on a spectrum with their other products.